Pure apraxic agraphia with recovery after drainage of a left frontal cyst.

A case is reported of isolated apraxia of writing in which general limb praxis was spared. Spontaneous writing, writing to dictation and copying were equally affected. Letter selection and spelling were preserved and other language functions intact. A CT scan revealed a left frontal arachnoid cyst. After surgical drainage the agraphia resolved. The anatomical basis of the disorder is discussed in the light of modern information processing models of writing.